Conventionally, in a radio communication system, various radio access schemes are employed. For example, in UMTS (Universal Mobile Telecommunications System), which is also referred to as “W-CDMA (Wideband Code Division Multiple Access),” code division multiple access (CDMA) is employed. Also, in LTE (Long Term Evolution), orthogonal frequency division multiple access (OFDMA) is employed (for example, non-patent literature 1).